含苯并咪唑环的1, 3, 4-噁二唑衍生物的核磁共振研究

在无水乙醇和KOH 存在下，将2-苯氧甲基苯并咪唑-1-乙酰肼(1)与CS₂反应，合成出了中间体5-(2-苯氧甲基苯并咪唑-1-亚甲基)-2-巯基-1,3,4-噁二唑(2)，此中间体再与氯乙酰苯胺反应，得到一种新化合物-N-苯基-2-5-(2-苯氧甲基苯并咪唑-1-亚甲基)-1,3,4-噁二唑-2-硫基]乙酰胺(3). 采用元素分析、IR及NMR技术确定了新化合物3的结构，并利用2D NMR技术对其trans和cis两种异构体的¹H和¹³C NMR谱带进行了全归属，给出了相应的偶合常数J值以及异构体所占的比例. 实验表明，新化合物3在DMSO中存在着trans和cis两种异构体的互变，并且trans异构体占主导，含量为64.5%， 而cis异构体的含量为35.5%.

An NMR Study of A Novel 1,3,4-Oxadiazole Derivative Containing Benzimidazole Moiety

A new compound, N-phenyl-2-({5-(2-(phenoxymethyl)-benzimidazol-1-yl)methyl]-1, 3, 4-oxadiazol-2-yl}thio) acetamide (3), was synthesized by the reaction of 5-{2-(phenoxymethyl)-benzimidazol-1-yl]methyl}-2-thiol-1,3, 4-oxadiazole (2) with N-phenyl-2-chloro-acetamide. The compound2 was obtained by the reaction of the hydrazide (1) with carbon disulfide in the presence of absolute ethanol and potassium hydroxide. The structure of the new compound 3 was determined by elemental analysis, IR and NMR techniques. The ¹H and ¹³C NMR signals of the two isomers (trans and cis) of compound 3 were assigned using 2D NMR techniques. The corresponding coupling constants and the tautomeric ratios of isomers were calculated. The ratio of the dominant trans isomer was 64.5%, while the cis isomer was 35.5%.